Eveningness and poor sleep quality contribute to depressive residual symptoms and behavioral inhibition in patients with bipolar disorder

ABSTRACT

Eveningness and sleep disturbances are considered as markers of Bipolar Disorder (BD) and influence mood and emotional or behavioral states. This study investigates the associations between circadian markers and sleep quality on residual depressive symptoms and inhibition/activation dimensions during the euthymic phase. A sample of 89 euthymic adult individuals with BD was assessed for circadian preference and typology using the Composite Scale of Morningness (CSM) and the Circadian Type Inventory (CTI) and for sleep quality using the Pittsburgh Sleep Quality Index (PSQI). The Montgomery and Asberg Depression Rating Scale (MADRS) and the Multidimensional Assessment of Thymic States (MAThyS) were used to measure residual depressive symptoms and the inhibition/activation dimensions. We examined any associations between these parameters using correlations and path analyses. We identified significant associations between eveningness and poorer sleep quality that correlated to higher depressive residual symptoms and a global inhibition. The use of path analyses led us to conclude that poor sleep quality mediated the relationship between eveningness and either residual mood symptoms or behavioral inhibition (motivation, sensory perception, interpersonal interaction, and cognition). These factors should be considered in the clinical evaluation of individuals with BD, with a specific attention during the euthymic phase, in order to achieve the best functional outcome possible.

KEYWORDS:

• Eveningness
• sleep quality
• inhibition/activation
• depressive symptoms
• bipolar disorder

Acknowledgments

We thank the individuals with BD who agreed to participate in this study. We thank the staff at the inclusion sites in Paris Fernand-Widal/Lariboisière and Paris-Creteil (France).

Declaration of interest statement

The authors report no financial affiliation or other relationship relevant to the subject matter of this article.

Supplementary Material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by Institut National de la Santé et de la Recherche Médicale (INSERM – Research Protocol C0829), Assistance Publique des Hôpitaux de Paris (APHP – Research Protocol GAN12). This research was also supported by the Investissements d’Avenir program managed by the Agence Nationale de la Recherche (ANR) under reference ANR-11-IDEX-0004 and Fondation FondaMental (RTRS Santé Mentale)